Japanese version of the Brief Sense of Community Scale: construct validity and reliability

Background The Brief Sense of Community Scale is a widely accepted eight-item scale that measures the four dimensions of sense of community; however, the factor structure of the Japanese version of this scale has never been confirmed. In this study, we demonstrated the reliability and validity of the Japanese version of the Brief Sense of Community Scale. Methods After completing the back translation of the scale, a sample of 993 Japanese individuals completed the Japanese version of the Brief Sense of Community Scale. Results The results indicate that the Japanese version of the Brief Sense of Community Scale is comparable to the original scale and demonstrated adequate goodness-of-fit for both the four-factor and second-order models, which demonstrates its validity. Nonetheless, it remains necessary to consider possible cross-national cultural concerns when utilizing the scale. Conclusions The Japanese version of the Brief Sense of Community Scale will contribute toward the creation of a community in which all members feel comfortable.

items, which can be utilized in various community contexts, has been raised [2,5].
To address these problems, Peterson et al. [5] created the Brief Sense of Community Scale (BSCS) and confirmed its reliability and validity. Comprising only eight items, the BSCS can not only measure the four SOC dimensions proposed by McMillan and Chavis [1] but can also represent a robust factor structure [5].
Recently, BSCS has gained attention for its applicability in various community studies, such as those among youth [6,7], LGBT individuals [8], and residents [5]; moreover, it has been translated to several non-English languages [9]. BSCS is widely used in Asia, including China [10][11][12][13], Korea [14], Vietnam [15], and Japan [16], as well as in the Western community. However, problems exist in the BSCS used in Asia, such as the translation process being unclear [10][11][12][13][14][15][16][17][18][19] and back translate being performed but not examined for validity [20]. In addition, the factor structure of the BSCS has not been examined, and many studies use the BSCS as a one-factor [10][11][12][13][14][15][16][17][18][19][20]. We believe that it is necessary to clarify the factor structure of the BSCS in Asia and to verify its validity to make cross-national comparisons with the Western community. We conducted the present study in Japan as the first step, and the findings can be compared with those in other regions of Asia in the future.
It is noteworthy that the most SOC studies in Japan developed their own measures instead of adopting Western ones [21][22][23]. This is because the strong influence of Japan's unique socio-cultural contexts, such as "ie" (household) and "mura" (village community), can hinder the accurate translation of a measure to Japanese [21]. Nonetheless, the independent measures developed in Japan cannot be considered suitable for application in future cross-national studies on SOC. The Japanese version of the BSCS will resolve this issue of the generalization of SOC measurements.
Considering this situation, we developed a Japanese version of the BSCS and examined its reliability and validity within a sample of Japanese community residents. To verify the "criterion-related validity, " we also used the Sense of Community Scale 2 (SCI-2), Community Consciousness Scale (CCS [21,22]), and Center for Epidemiologic Studies Depression Scale (CES-D [24]). Below, we briefly explain why each of the three scales were used for the criterion-related validity test.
(i) SCI-2: As a McMillan-Chavis four-factor structure was confirmed in SCI-2 by increasing the number of items, eliminating inverted items, and making changes to the required responses, it is expected that all factors of SCI-2 would be positively cor-related with those of the Japanese version of the BSCS. (ii) CCS: CCS is a widely accepted measure of SOC that was developed in Japan and includes the roles of the government and initiatives by citizens of the community. [21,22] (iii) CES-D: SOC has been shown to improve an individual's mental health [1,25,26], and CES-D, a measure of depression, is negatively correlated with BSCS. [5,11,12,18]

Participants
The survey was outsourced to an online survey agency (Cross Marketing Co., Ltd.  [27]. Thus, both regions are geographically and culturally different. As the Chubu region can be considered either to the east or the west [28], it was classified as the western region in this study.

Japanese version of the BSCS
The BSCS, created by Peterson et al. [5], comprises eight items scored on a 5-point Likert-type scale (ranging from 1 = strongly disagree to 5 = strongly agree) to assess the four dimensions of SOC (needs fulfilment, membership, influence, and emotional connection). The scale's reliability was confirmed by an internal consistency of Cronbach's α = 0.85 ~ 0.92 [5,7]. We translated the BSCS into Japanese after obtaining permission and performed the standard procedure of back-translation with advice from Dr. Peterson.

Sense of Community Index 2 (SCI-2)
SCI-2 is a 24-item self-report scale that adopts the theoretical framework of McMillan and Chavis [1]; its four subscales are "reinforcement of needs, " "membership, " "influence, " and "shared emotional connection. " [29] The scale's reliability was confirmed by an internal consistency of Cronbach's α = 0.91 for the entire scale and 0.79 ~ 0.86 for the subscales [30].The SCI-2 items are scored on a 4-point Likert scale ranging from 0 (not at all) to 3 (completely), with six items under each subscale.

Short version of Community Conscious Scale
The short version of community conscious scale is a 12-item self-report questionnaire [22]. This scale is a short version of the CCS [21,31] considers SOC to be a multifaceted concept that included the roles of government and citizen agency in the community. The items are scored on a 5-point Likert-type scale ranging from 1 (disagree) to 5 (agree). This scale comprises the following four subscales, each including three items: solidarity (e.g., "I want to participate in voluntary activities in my community"), self-determination (e.g., "In the problem solving in the community, it is important to build up an equal partnership between the residents and administration"), attachment (e.g., "Because I live temporarily in this community, I have neither the concern of nor the attachment to my community"), and dependency on others (e.g., "It is acceptable that the residents leave the activities in improving their living environment in the community to more dedicated people").

Japanese version of the Center for Epidemiologic Studies Depression (CES-D)
The Japanese version of the CES-D is a 20-item selfreport scale that measures depression under the following four subscales: "somatic complaints, " "depressed affect, " "positive affect, " and "interpersonal problems" [32]. Participants respond to the 20 items based on their experiences within the past week on a 4-point Likert scale ranging from 0 (rarely or none of the time, less than 1 day) to 3 (most or all the time, 5-7 days).

Procedures
This study was approved by the Ethics Committee of the authors' university. Participation was entirely voluntary. Before administering the questionnaire, the participants were informed of the survey overview and terms of confidentiality, and their consent was obtained. Cross Marketing awarded the participants with reward points for completing the questionnaire.

Statistical analyses
Confirmatory factor analysis (CFA) was performed using the Mplus 8.1 statistical software package [33]. Additionally, the maximum likelihood estimator (ML) was applied for CFA estimation in this study. To test the goodness-of-fit, we conducted comparative fit index (CFI), Tucker-Lewis index (TLI), root mean square error of approximation (RMSEA), standardized root mean square residual (SRMR), Akaike's information criterion (AIC), Bayesian information criterion (BIC), and Akaike's Bayesian information criterion (ABIC). The cut-off values for acceptable model fit used in this study are: RMSEA ≧ 0.10 for poor fit and < 0.06 for good fit; CFI > 0.90 for acceptable fit and > 0.95 for good fit; and SRMR < 0.10 for acceptable fit and < 0.08 for good fit [34,35]. For additional analyses, multiple-group CFA was conducted to examine gender and region of residence (eastern or western region) invariance. Furthermore, measurement invariance was tested by creating three models: a configural model (no constraints), metric invariance model (with item loading constraints to be equal across groups), and scalar invariance model (with item loadings and item intercepts with simultaneous constraints to be equal across groups). Following the hierarchy of these nested models, they were compared with each other. We focused on the ratio of χ 2 to its degree of freedom, ΔCFI, ΔRMSEA and ΔSRMR as indicators in the model comparisons. Model invariance is indicated by Δχ 2 /Δdf of less than or equal to 5 and ΔCFI smaller than 0.01, accompanied by ΔRMSEA smaller than 0.015 and ΔSRMR smaller than 0.03 [36][37][38]. For the comparison of factor means, we followed guidelines [39] and demonstrated ΔM and p-value.
Other analyses were conducted using the program R version 3.6.3 [40]. Cronbach's alpha coefficients, McDonald's omega coefficients, and correlations between the Japanese BSCS and other measures were established by calculating the Pearson's correlation coefficients. All statistical analyses used two-tailed tests. For all statistical evaluations, p values less than 0.05 were considered indicative of significant differences.

Factor structure
The mean scores for each item of the Japanese BSCS are shown in Table 1. The mean values for each item ranged 2.33-3.10, with standard deviations ranging 0.91-1.04. Skewness and kurtosis were smaller than 1. Confirmatory factor analyses were used to examine the goodness-offit. Based on the original scale validation study [5], three models were tested for use among Japanese participants (Fig. 1). As shown in Table 2, the four-factor and secondorder models demonstrated acceptable fits, whereas the one-factor case did not. Therefore, although the secondorder model had higher AIC, BIC, and ABIC than the four-factor model, we will examine the gender and region of residence invariances for both.
Multiple-group CFA was performed to examine the gender and region of residence invariances in both models. In the four-factor model, the metric invariance and configural models showed acceptable cutoff criteria (gender: Δχ 2 /Δdf  ΔSRMR = − 0.001). Therefore, the scalar invariance model was supported in the second-order model as well (Table 3). Finally, the factor means were compared between genders. In the four-factor model, women had lower factor means than men for both IN  Meanwhile, in the second-order model, the western region had higher factor means than eastern region, which were not significant (ΔM = 0.08, p = 0.23).Thus, we did not find differences between the factor means of men and women, in the eastern and western regions either in the four-factor or the secondorder models.

Discussion
We developed the Japanese version of the BSCS and confirmed its four subscales-"needs fulfilment, " "membership, " "influence, " and "emotional connection"-through analyses of its factor. For the factor structure, acceptable goodness-of-fit was confirmed in both the four-factor and second-order models. The multiple-group CFA by gender and region of residence found identical factor structures and non-differentiable factor loadings and intercept. Additionally, the factor means were not differentiable in the four-factor and second-order models. The BSCS has represented the same factor structures across various samples, such as in midwestern United states neighborhood residents [5], youth [6,7], and LGB individuals [8]. Therefore, the factor structure of BSCS may show demonstrate robustness even in communities within different cultures and demographics. We also note that the four-factor and second-order models in this study, in addition to the previous study cases [5][6][7][8], showed adequate goodness-of-fit. Let us discuss the correlations between the Japanese version of the BSCS and other measures, which can indicate acceptable reliability and validity of the Japanese BSCS. First, the significantly positive correlations between each factor of the BSCS and all factors of the SCI-2 indicate that the Japanese version of the BSCS corresponds to the four dimensions of McMillan and Chavis [1]. Second, in the correlations between the BSCS and CCS, we found that "solidarity, " "self-determination, " and "attachment" in the CCS were positively correlated with all factors of the BSCS; additionally, "dependence on others" in the CCS demonstrated a negative correlation with only "group membership" in the BSCS. As "dependency on others" is a factor that indicates an indifference toward local issues and reliance on unknown others to solve them [21,22,31], it is possible that the feeling of being a part of the community results in a decrease in the indifference toward the community. Third, CES-D was negatively correlated with the BSCS. This indicates that a sense of community is related to individual mental health in Japan, as in previous studies [5,25,26]. It is also remarkable that the correlations between the Japanese version of the BSCS and the demographic variables were generally consistent with those in previous studies [5,8], and that the Japanese version of the BSCS had a factor structure in common with cases in previous studies [5][6][7][8]. Taken together, these results suggest that the BSCS has a robust factor structure, even across different cultures.

Limitations
This study has some limitations. We note that the relationships between the SOC and "community participation" could not be evaluated. As local activities remain restricted due to COVID-19 in Japan [41], we did not continue to measure community participation as it may mislead further analysis. We hope that future studies will analyze the community participation from the perspective of the SOC.
The second limitation is that comparisons by place of residence could only be made for the broad categories of the eastern and western regions. In this study, respondents were asked about their place of residence, but only up to prefecture. It is possible that SOC may differ between those who live in urban areas and those who live in rural areas, even in the same prefecture. In the future, it will be necessary to examine differences by size of cities of residence and type of community, such as rural or urban.
The third limitation is related to the survey methodology; we used an online survey agency to collect data from participants of various ages and living across different areas of Japan. However, nonprobability online surveys, as in this study, have been noted to be less accurate than probability telephone and online surveys [42]. Therefore, it may be necessary to conduct a probability survey, or a survey of all members of a particular local community, to examine whether a similar factor structure can be obtained.
Finally, as this study was conducted on Japanese participants, it remains unclear whether the factor structure identified in the present study is also observed in other countries, particularly in Asia. In the future, it will be necessary to clarify the factor structure of the BSCS through cross-national comparisons.